1. Field of the Invention
The present invention relates to a cooling air supply apparatus of a refrigerator, and more particularly, to a cooling air supply apparatus of a refrigerator that is capable of efficiently supplying cooling air from a freezing compartment of the refrigerator to a receiving box formed in a refrigerating compartment of the refrigerator for storing vegetables and meat.
2. Discussion of the Related Art
Generally, a refrigerator is an electric appliance that stores food at relatively low temperature to prevent the food from rotting and to maintain the food in a fresh state. The refrigerator typically includes a refrigerating compartment for storing the food in a refrigerated state at above-zero low temperature (normally 0° C. to 8° C.) and a freezing compartment for storing the food in a frozen state at sub-zero low temperature (normally −20° C. to −0° C.)
In recent years, a side-by-side type refrigerator, wherein a refrigerating compartment and a freezing compartment are arranged in the width direction of the refrigerator in order to improve the receiving efficiency of the refrigerator, has been increasingly used. Even in this side-by-side type refrigerator, the refrigerating compartment and the freezing compartment, which are arranged in the width direction of the refrigerator, are partitioned from each other by a barrier in the same manner as conventional refrigerators.
Generally, it is preferable that some of food stored in the refrigerator, for example, vegetables and fruits, be stored at approximately 4° C. Also, it is preferable that vegetables and fruits be stored in the refrigerator in such a manner that the evaporation of moisture from the vegetables and the fruits can be effectively prevented in consideration of the characteristics of the vegetables and the fruits. To this end, an additional receiving box is mounted in a hermetically-sealed state at one side of the refrigerator for storing the vegetables and the fruits without loss of moisture.
Furthermore, in recent years, there has been developed a method of storing meat in the refrigerating compartment of the refrigerator in an unfrozen state, thereby insuring relatively minor deterioration of taste and nutriment, in addition to a conventional method of storing meat in the freezing compartment of the refrigerator in a frozen state such that the meat can be frozen at a low temperature of approximately 18° C. below zero.
In this method of storing the meat in the unfrozen state, the meat is stored at a temperature of approximately 1° C. below zero. Consequently, the method of storing the meat in the unfrozen state has an advantage in that not only the spoilage or deterioration of the meat is prevented but also the damage to taste and nutriment is minimized.
Hereinafter, a conventional side-by-side type refrigerator and a structure for supplying cooling air to a receiving box of the refrigerator will be described in brief with reference to FIGS. 1 to 3.
First, as shown in FIG. 1, a freezing compartment 11 and a refrigerating compartment 12 are arranged in a refrigerator body 10 in the width direction of the refrigerator. Between the refrigerating compartment 12 and the freezing compartment 11 is disposed a barrier 13, by which the refrigerating compartment 12 and the freezing compartment 11 are partitioned from each other.
Inside the refrigerating compartment 12 are mounted a plurality of receiving boxes 20, which can be moved in forward and backward directions of the refrigerator, i.e., to the outside and inside of the refrigerator body 10, such that food can be easily put into the receiving boxes 20 and food can be easily taken out of the receiving boxes 20. Each of the receiving boxes 20 has an open top part, which is covered by a corresponding one of shelves 30 that divide the refrigerating compartment into a plurality of refrigerating sections.
Consequently, while the interior of the refrigerating compartment 12 of the refrigerator body 10 is maintained at an appropriate temperature, i.e., approximately 4° C. above zero, the interior of each receiving box 20 is also maintained at approximately 4° C. above zero such that vegetables and fruits can be stored in a fresh state in each receiving box 20. At this time, when the open top part of each receiving box 20 is covered by the corresponding shelf 30, the evaporation of moisture from the vegetables and the fruits can be effectively prevented, and therefore, the vegetables and the fruits can be stored for a long period of time in a fresh state.
As described above, in recent years, there has been proposed a method of storing meat in any one of the receiving boxes 20 mounted in the refrigerating compartment 12 in an unfrozen state by supplying cooling air to the receiving box 20.
FIGS. 2 and 3 illustrate a conventional structure for selectively supplying cooling air from the freezing compartment to the receiving box 20 of the refrigerating compartment 12. Specifically, as shown in FIGS. 2 and 3, a communication port 40 is formed through the lower part of the barrier 13, which partitions the refrigerating compartment 12 and the freezing compartment 11 from each other, such that cooling air can be supplied from the freezing compartment 11 to the receiving box 20 mounted in the refrigerating compartment 12 through the communication port 40. As a result, the interior of the receiving box 20 can be maintained at a temperature of approximately 1° C. below zero, which is lower than the overall temperature of the refrigerating compartment 12, whereby meat can be stored in the unfrozen state.
The amount of cooling air passing through the communication port 40 is controlled by the adjustment of the open sectional area of the communication port 40, which is performed by the operation of a temperature control unit and a damper (not shown) of the refrigerating compartment 12.
The control of the amount of cooling air passing through the communication port 40 will be described in more detail below.
When a user puts meat into the receiving box 20, and manipulates a controller (not shown) such that the interior of the receiving box 20 can be maintained in an unfrozen state, i.e., at a temperature of approximately 1° C. below zero, the damper (not shown) formed at the communication port 40 is opened, and therefore, cooling air is supplied from the freezing compartment 11 to the refrigerating compartment 12 through the communication port 40.
The cooling air supplied through the communication port 40 is discharged into the refrigerating compartment 12, and then flows to one side of the receiving box 20. The cooling air having flowed to one side of the receiving box 20 subsequently flows to the upper and lower parts and front and rear parts of the receiving box 20 through a space defined between the receiving box 20 and the inner wall of the refrigerating compartment 12.
The cooling air flowing along the outside of the receiving box 20 is introduced into the receiving box 20 through cooling air supplying holes 20a formed in the side part or the rear part of the receiving box 20. As a result, the interior temperature of the receiving box 20 is lowered, and therefore, the meat received in the receiving box 20 is stored at a predetermined temperature, at which the meat is stored in an unfrozen state.
However, the conventional cooling air supply apparatus for supplying the cooling air from the freezing compartment 11 to the receiving box 20 of the refrigerating box 12 has the following problems.
First, when the cooling air flowing through the communication port 40 is supplied to one side of the receiving box 20, the supplied cooling air flows along the outside of the receiving box 20. At this time, heat transfer is carried out between a part of the cooling air and the air in the refrigerating compartment 12, which is higher than the cooling air. As a result, the cooling air is supplied into the receiving box 20 while the temperature of the cooling air slightly increases.
Consequently, there is generated a temperature variation between the temperature of the cooling air introduced through the cooling air supplying hole 20a relatively adjacent to the communication port 40 and the temperature of the cooling air introduced through the cooling air supplying hole 20a relatively far away from the communication port 40. As a result, the interior temperature of the receiving box 20 cannot be uniformly maintained, and therefore, the cooling efficiency in the receiving box 20 is lowered.
Secondly, the cooling air flowing through the communication port 40 is not directly supplied into the receiving box 20. The cooling air flowing through the communication port 40 collides with one side of the receiving box 20, and then flows along the outside of the receiving box 20. As a result, loss of cooling air is incurred, and the temperatures of other components in the vicinity of the receiving box 20 are also lowered.
For example, when cooling air having a temperature of approximately 7° C. below zero flows to the first part of the receiving box 20 through the communication port 40, beverages received inside a refrigerator door, which is disposed adjacent to the front part of the receiving box 20, may be frozen.
Thirdly, the cooling air flowing through the communication hole 40 is introduced into the receiving box 20 through a small number of cooling air supplying holes 20a formed at predetermined positions of the side part and rear part of the receiving box 20. As a result, food received in the receiving box 20 while being adjacent to the cooling air supplying holes 20a is greatly affected by the cooling air, but food received in the receiving box 20 while being far away from the cooling air supplying holes 20a is slightly affected by the cooling air. Consequently, it is difficult to uniformly store food in the receiving box 20.